1. Field of the Invention
This invention is directed to cementitious compositions, and methods of making cementitious compositions in which certain chemicals are pre-mixed.
2. Description of Related Art
A variety of cement additives are commercially available for enhancing the structural properties of cement. However, when the compressive strength of cement is increased, the cement typically becomes less flexible and more brittle. Consequently, tensile strength also decreases as the compressive strength is increased. Thus, optimization of the structural properties of cement compositions typically involves a compromise between compressive strength, flexibility, and tensile strength.
Heavy, pre-cast concrete products, such as bridges and roads, typically include reinforcements, such as steel reinforcement bars or steel mesh, or entail pre-stress methods such as tightening an embedded cable while the concrete is curing. These reinforcements are necessary because of the need to balance compressive strength with flexibility and tensile strength. For the same reasons, large, thin sheets of unreinforced concrete are generally impractical due to either the brittleness or weakness inherent in such structures.
The process of making cementitious compositions can be time-consuming, particularly when attempting to enhance (and balance) the structural properties of the composition with various commercially available additives.
Accordingly, there is a need or desire for a cementitious composition that can achieve high compressive strength while also achieving high flexibility and tensile strength. There is a further need or desire for cementitious compositions that can be used to make large structures, such as roads and bridges, without requiring added reinforcement. There is yet a further need or desire for cementitious compositions that can be used to make large, thin sheets that are relatively flexible. There is still a further need or desire for an efficient method of making cementitious compositions.